Limited write endurance is one of the
factors that detractors bring up with regards to solid state drives
(SSDs). Most NAND
flash chips using multi-level cell (MLC)technology in SSDs have a
write endurance of around 10,000 cycles. That isn't as great a
problem in SSDs greater than 120GB that use wear-leveling technology,
but smaller sized SSDs have less capacity and will reach the upper
limit much quicker.

That issue is why almost all SSDs aimed at
the corporate and enterprise market use Single Level Cell flash
chips, which typically have a write endurance around the 100,000
cycle mark. These include Intel's X25-E, OCZ's Vertex EX and Agility
EX series, and Super
Talent's MasterDrive RX series.

Micron Technology is one
of the key partners in IM Flash Tech along with Intel Corporation.
IMFT produces the 34nm NAND flash used in Intel's
second generation X25-M SSDs using 2-bit-per-cell MLC chips.
Micron and IMFT have been working on improving the write endurance of
their NAND chips, and they have now reached a breakthrough.

“By
leveraging our mature 34nm NAND process, Micron has developed
Enterprise NAND products that support customers’ high-endurance
requirements. These products ensure that enterprise organizations
have a highly reliable NAND flash solution – be it MLC or SLC –
for design into the broader enterprise storage platform,” said
Brian Shirley, Vice President of Micron’s memory group.

The
company’s new 32Gb MLC Enterprise NAND devices achieve an
impressive 30,000 write cycles. They are also introducing a 16Gb SLC
Enterprise NAND device that achieves 300,000 write cycles. The new
chips also support the ONFI
2.1 synchronous interface, making them easier to integrate into
new products.

Both of these new chips are built on the 34nm
process which IMFT introduced last year, and can be configured into
multi-die, single packages supporting densities of up to 32GB for MLC
NAND and 16GB for SLC NAND.

Micron is now sampling its
Enterprise NAND products with customers and controller manufacturers,
and is expected to enter volume production at the beginning of 2010.

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This article is over a month old, voting and posting comments is disabled

Whatever points you're trying to make gets drowned in the noise of your needless and unprovoked hostility and rudeness. If you'd behave like a normal person, more people would listen to what you have to say and judge your words more on their own merits, rather than the way you say them.

Also, most files may be larger than 128kb, but any person who actually knows anything about disk performance know that access time is indeed the vastly more important figure in almost every situation. Why else do you think enterprise drive arrays are comprised of relatively low-capacity high spindle speed drives? It's to cut down on read/write latency, of course.

Most disk accesses are on the order of 32kb-ish per I/O request, not many megabytes, and a HDD reads or writes that amount in (for argument's sake) a microsecond. Problem is, it takes a thousand times longer or more to actually seek to that sector and wait for the heads to settle... That's the HDD's achilles heel.

If all you do is read or write the occasional large or small file, then neither access time OR transfer speed is really all that important, because even a large file will be transferred quickly with any reasonably modern harddrive (within one or a few seconds at most, typically), and this very slight delay is tiny tiny compared to the full workday.

However, if the system experiences heavy disk activity, then the picture changes noticably with access time dominating hugely unless all you do is simple linear reading/writing (such as video editing, for example). I can just use myself as an example, my main rig starts up roughly 15 apps on bootup (and a multitude of background services and whatnot). With a standard HDD, it took about half a minute if not more of waiting before disk activity settled down to a level where the PC became responsive. When I switched to an Intel SLC SSD, the PC is fully responsive about 2-3 seconds after typing in the password. Basically, I can use the system normally by the time I've moved my hand from the keyboard to the mouse upon logging in!

Hybrid harddrives get ignored mostly because they're neither fish nor fowl, but rather a half-assed half-measure that does not fully share the advantages of either tech they try to combine. It's not nearly as fast as a dedicated SSD, and at the same time not as cheap as a standard harddrive. Add the complexities of managing the flash cache as best as possible, wear leveling complications, more parts that can fail and so on and then the difficulties of trying to explain the benefits of your new hybrid harddrive to a mostly ignorant herd of customers (consumers as well as enterprise), and I think you too will see how HDD makers find the extra expense in hybrid R&D not really worth the bother...